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sentry_options/
schema_fetch.rs

1//! Fetch schema snapshots from the repositories listed in `repos.json`.
2//!
3//! This is an explicit tooling API. The options runtime remains file-based and
4//! never fetches schemas as part of initialization or value reads.
5
6use serde::Deserialize;
7use std::collections::HashMap;
8use std::fs;
9use std::path::Path;
10use std::process::Command;
11use std::thread;
12use std::time::Duration;
13use thiserror::Error;
14
15#[derive(Debug, Error)]
16pub enum SchemaFetchError {
17    #[error("{0}")]
18    Validation(String),
19
20    #[error("I/O error: {0}")]
21    Io(#[from] std::io::Error),
22
23    #[error("JSON error: {0}")]
24    Json(#[from] serde_json::Error),
25
26    #[error("Git command failed: {0}")]
27    Git(String),
28}
29
30pub type SchemaFetchResult<T> = std::result::Result<T, SchemaFetchError>;
31
32#[derive(Debug, Deserialize)]
33#[serde(deny_unknown_fields)]
34pub struct RepoSchemaConfig {
35    pub url: String,
36    /// Optional repository pin retained for compatibility with `repos.json`.
37    /// Schema snapshots currently follow the repository's default branch.
38    #[allow(dead_code)]
39    #[serde(default)]
40    pub sha: Option<String>,
41    pub path: String,
42}
43
44#[derive(Debug, Deserialize)]
45#[serde(deny_unknown_fields)]
46pub struct RepoSchemaConfigs {
47    pub repos: HashMap<String, RepoSchemaConfig>,
48}
49
50impl RepoSchemaConfigs {
51    pub fn from_file(path: &Path) -> SchemaFetchResult<Self> {
52        let content = fs::read_to_string(path)?;
53        Ok(serde_json::from_str(&content)?)
54    }
55}
56
57/// Fetch every configured repository's schemas into a new directory.
58pub fn fetch_schemas(config: &RepoSchemaConfigs, out_dir: &Path) -> SchemaFetchResult<()> {
59    if out_dir.exists() {
60        return Err(SchemaFetchError::Validation(format!(
61            "Output directory already exists: {}",
62            out_dir.display()
63        )));
64    }
65    fs::create_dir_all(out_dir)?;
66
67    // Sort repo names for deterministic error reporting.
68    let mut repo_names: Vec<_> = config.repos.keys().collect();
69    repo_names.sort();
70
71    let results: Vec<_> = thread::scope(|scope| {
72        let handles: Vec<_> = repo_names
73            .iter()
74            .map(|repo_name| {
75                let source = &config.repos[*repo_name];
76                let name = repo_name.as_str();
77                (
78                    name,
79                    scope.spawn(move || fetch_repo_schemas(name, source, out_dir)),
80                )
81            })
82            .collect();
83
84        handles
85            .into_iter()
86            .map(|(name, handle)| {
87                let result = match handle.join() {
88                    Ok(Ok(())) => Ok(()),
89                    Ok(Err(error)) => Err(error.to_string()),
90                    Err(_) => Err(format!("{}: thread panicked", name)),
91                };
92                (name, result)
93            })
94            .collect::<Vec<_>>()
95    });
96
97    let mut errors = Vec::new();
98    for (_repo_name, result) in results {
99        match result {
100            Ok(()) => {}
101            Err(error) => errors.push(error),
102        }
103    }
104
105    if errors.is_empty() {
106        Ok(())
107    } else {
108        Err(SchemaFetchError::Git(errors.join("\n")))
109    }
110}
111
112/// Read `repos.json` and fetch its configured schemas.
113pub fn fetch_schemas_from_file(config_path: &Path, out_dir: &Path) -> SchemaFetchResult<()> {
114    let config = RepoSchemaConfigs::from_file(config_path)?;
115    fetch_schemas(&config, out_dir)
116}
117
118const MAX_RETRIES: u32 = 3;
119const INITIAL_RETRY_DELAY: Duration = Duration::from_secs(3);
120
121fn fetch_repo_schemas(
122    repo_name: &str,
123    source: &RepoSchemaConfig,
124    out_dir: &Path,
125) -> SchemaFetchResult<()> {
126    let mut delay = INITIAL_RETRY_DELAY;
127    let mut last_error = None;
128
129    for attempt in 0..=MAX_RETRIES {
130        if attempt > 0 {
131            thread::sleep(delay);
132            delay *= 2;
133        }
134
135        match try_fetch_repo_schemas(repo_name, source, out_dir) {
136            Ok(()) => return Ok(()),
137            Err(error) => last_error = Some(error),
138        }
139    }
140
141    Err(last_error.expect("at least one fetch attempt must run"))
142}
143
144fn try_fetch_repo_schemas(
145    repo_name: &str,
146    source: &RepoSchemaConfig,
147    out_dir: &Path,
148) -> SchemaFetchResult<()> {
149    let temp_dir = tempfile::tempdir()?;
150    let repo_path = temp_dir.path().join("repo");
151    let repo_str = repo_path.to_str().ok_or_else(|| {
152        SchemaFetchError::Validation(format!("{}: temp path contains invalid UTF-8", repo_name))
153    })?;
154
155    git(
156        &[
157            "clone",
158            "--filter=blob:none",
159            "--sparse",
160            &source.url,
161            repo_str,
162        ],
163        None,
164        repo_name,
165    )?;
166    git(
167        &["sparse-checkout", "set", &source.path],
168        Some(&repo_path),
169        repo_name,
170    )?;
171
172    copy_schemas(&repo_path.join(&source.path), out_dir)
173}
174
175fn git(args: &[&str], cwd: Option<&Path>, repo_name: &str) -> SchemaFetchResult<()> {
176    let mut command = Command::new("git");
177    command.args(args);
178    if let Some(directory) = cwd {
179        command.current_dir(directory);
180    }
181    let output = command.output()?;
182    if output.status.success() {
183        Ok(())
184    } else {
185        Err(SchemaFetchError::Git(format!(
186            "{}: {}",
187            repo_name,
188            String::from_utf8_lossy(&output.stderr).trim()
189        )))
190    }
191}
192
193fn copy_schemas(src: &Path, dest: &Path) -> SchemaFetchResult<()> {
194    if !src.exists() {
195        return Err(SchemaFetchError::Validation(format!(
196            "Schemas path does not exist: {}",
197            src.display()
198        )));
199    }
200
201    for entry in fs::read_dir(src)? {
202        let entry = entry?;
203        if entry.file_type()?.is_dir() {
204            let namespace = entry.file_name();
205            let src_schema = entry.path().join("schema.json");
206            if src_schema.exists() {
207                let dest_namespace = dest.join(&namespace);
208                fs::create_dir_all(&dest_namespace)?;
209                fs::copy(src_schema, dest_namespace.join("schema.json"))?;
210            }
211        }
212    }
213    Ok(())
214}
215
216#[cfg(test)]
217mod tests {
218    use super::*;
219    use tempfile::TempDir;
220
221    #[test]
222    fn test_from_file_valid_json() {
223        let dir = TempDir::new().unwrap();
224        let path = dir.path().join("repos.json");
225        fs::write(
226            &path,
227            r#"{
228                "repos": {
229                    "sentry": {
230                        "url": "https://github.com/getsentry/sentry",
231                        "sha": "abc123",
232                        "path": "schemas/"
233                    }
234                }
235            }"#,
236        )
237        .unwrap();
238
239        let config = RepoSchemaConfigs::from_file(&path).unwrap();
240        assert_eq!(config.repos.len(), 1);
241        let sentry = config.repos.get("sentry").unwrap();
242        assert_eq!(sentry.url, "https://github.com/getsentry/sentry");
243        assert_eq!(sentry.sha, Some("abc123".to_string()));
244        assert_eq!(sentry.path, "schemas/");
245    }
246
247    #[test]
248    fn test_from_file_rejects_unknown_fields() {
249        let dir = TempDir::new().unwrap();
250        let path = dir.path().join("repos.json");
251        fs::write(
252            &path,
253            r#"{
254                "repos": {
255                    "sentry": {
256                        "url": "https://github.com/getsentry/sentry",
257                        "path": "schemas/",
258                        "unknown_field": true
259                    }
260                }
261            }"#,
262        )
263        .unwrap();
264
265        let error = RepoSchemaConfigs::from_file(&path).unwrap_err();
266        assert!(error.to_string().contains("unknown field `unknown_field`"));
267    }
268
269    #[test]
270    fn test_copy_schemas() {
271        let src_dir = TempDir::new().unwrap();
272        let dest_dir = TempDir::new().unwrap();
273        let namespace = src_dir.path().join("relay");
274        fs::create_dir_all(&namespace).unwrap();
275        fs::write(namespace.join("schema.json"), r#"{"version": "1.0"}"#).unwrap();
276
277        copy_schemas(src_dir.path(), dest_dir.path()).unwrap();
278
279        assert!(dest_dir.path().join("relay/schema.json").exists());
280    }
281
282    #[test]
283    fn test_fetch_schemas_errors_if_output_exists() {
284        let out_dir = TempDir::new().unwrap();
285        let config = RepoSchemaConfigs {
286            repos: HashMap::new(),
287        };
288
289        let error = fetch_schemas(&config, out_dir.path()).unwrap_err();
290        assert!(
291            error
292                .to_string()
293                .contains("Output directory already exists")
294        );
295    }
296}